Soil Characteristics Analysis in the Dupi Tila Formation of Sylhet for Engineering Applications

This research analyzes the geotechnical properties of the Dupi Tila Formation in Sylhet, Bangladesh, to assess its suitability for foundation design, slope stability and pavement construction. Laboratory tests, including analysis of particle size, Atterberg limits, Standard Proctor test, compressive strength, shear strength, and consolidation analyses, were conducted to determine key soil characteristics. Results indicate significant variability in soil properties: wet density (1.97–2.28 Mg/m³), dry density (1.60–1.91 Mg/m³), and water content (17.2–22.7%). The formation consists of fine sand, silt, and sand-gravel mixtures, with plasticity indices (3.4–27.1), indicating varying moisture sensitivity. California Bearing Ratio (CBR) values (6.8–9%) and ultimate bearing capacity (572.68–952 KPa) affect subgrade strength. The bearing capacity and slope stability of the Dupi Tila formation vary with cohesion, friction angle, and density. Dense, cohesionless sands with high friction angles support shallow foundations, while fine-grained soils may require reinforcement. In some cases, slope stabilization measures are necessary. Site-specific investigations are essential for designing stable foundations, retaining walls, and slope protection systems in the Dupi Tila Formation.